tools: remove git diff exit-code and lint the code

Author: fasenderos

tools/dep_updaters/update-zlib.sh

@@ -10,14 +10,12 @@ DEPS_DIR="$BASE_DIR/deps"
 echo "Comparing latest upstream with current revision"
 
 # Revert zconf.h changes before checking diff 
-perl -i -pe 's|^//#include "chromeconf.h"|#include "chromeconf.h"|' $DEPS_DIR/zlib/zconf.h
-git stash
+perl -i -pe 's|^//#include "chromeconf.h"|#include "chromeconf.h"|' "$DEPS_DIR/zlib/zconf.h"
+git stash -- "$DEPS_DIR/zlib/zconf.h"
+
 git fetch https://chromium.googlesource.com/chromium/src/third_party/zlib.git HEAD
 
-DIFF_TREE=$(
- git diff stash@{0}:deps/zlib FETCH_HEAD -- zconf.h
- git diff --exit-code --diff-filter=d HEAD:deps/zlib FETCH_HEAD -- ':!zconf.h' || echo 1
-)
+DIFF_TREE=$(git diff --diff-filter=d 'stash@{0}:deps/zlib' FETCH_HEAD)
 
 git stash drop
 
@@ -73,7 +71,7 @@ mkdir "$DEPS_DIR/zlib/win32"
 
 mv "$DEPS_DIR/zlib.def" "$DEPS_DIR/zlib/win32"
 
-perl -i -pe 's|^#include "chromeconf.h"|//#include "chromeconf.h"|' $DEPS_DIR/zlib/zconf.h
+perl -i -pe 's|^#include "chromeconf.h"|//#include "chromeconf.h"|' "$DEPS_DIR/zlib/zconf.h"
 
 echo "All done!"
 echo ""